1. Field of the Invention
The present invention relates generally to a driver circuit for a liquid crystal panel and LCD using the same, and more particularly to a driver circuit for a liquid crystal panel and LCD using the same, which can reduce unnecessary power consumption by shutting off power to the liquid crystal panel during a power saving mode.
2. Description of the Related Art
Recently, there is widely used a Thin Film Transistor-Liquid Crystal Display (TFT-LCD) that is lightweight, is small-sized and can implement full colors and high resolution compared to a Cathode Ray Tube (CRT) type display. Such TFT-LCDs are the display devices that exploit an optical characteristic of liquid crystals in which the molecular arrangement thereof is changed by an electric field, and are used as units for performing a display function in systems, such as notebook computers, televisions and monitors.
As shown in FIG. 1, a TFT-LCD 10 includes a backlight 20 having a light source, a liquid crystal panel 30 formed by injecting liquid crystals between combined upper and lower substrates, and a driver circuit 40 having data and gate driving unit 41 and 42 for driving the liquid crystal panel 30 and a timing controller 43 for generating control signals to control the driving units 41 and 42.
Although a TFT-LCD monitor to which the above-described TFT-LCD 10 is applied can use digital signals output from a computer body without conversion, an Analog Digital Converter (ADC) for converting analog signals into digital signals is employed to be compatible with existing graphic cards because most graphic cards currently use the way of converting digital signals output from the computer body into analog signals and outputting the converted analog signals.
However, since the conventional TFT-LCD monitor should be additionally equipped with the ADC and the like, the manufacturing costs thereof are increased. Additionally, since the processes of converting digital signals output from the computer body into analog signals in a graphic card and converting the converted analog signals into digital signals should be undergone, the conventional TFT-LCD monitor is problematic in that the distortion of screens may be caused by a signal loss and noise generated during the signal conversion processes.
In order to solve the problem, demands for digital type TFT-LCD monitors using digital signals output from a computer body without conversion are increased, and it is expected that the trend toward the increased demands will be further increased due to the popularization of graphic cards.
However, since the above-described conventional digital type TFT-LCD monitor is constructed so that power is supplied to a liquid crystal panel in a power saving mode, the conventional digital type TFT-LCD monitor is problematic in that power consumption is great, so that it is difficult to satisfy the Display Power Management System (DPMS) standard.
Additionally, the above-described digital type TFT-LCD monitor reduces unnecessary power consumption by blanking image being displayed so as to prevent a user from recognizing the input of an abnormal image signal when the abnormal image signal is input from a computer body. However, since the liquid crystal panel is still supplied with power during a blanking period, the conventional digital type TFT-LCD monitor is disadvantageous in that power consumption during the blanking period is the same as that during a normal operation.